1: 62 percent / trifluoroacetic acid / CH2Cl2 / 4 h 2: 90 percent / sodium borohydride, CeCl3 / methanol / 0.02 h 3: 82 percent / acetic acid / 1 h 4: 96 percent / hexamethyldisilazane / pyridine / 0.08 h 5: 54 percent / toluene / 2 h / 370 °C 6: 96 percent / aq. HCl / tetrahydrofuran / 0.08 h 7: 91 percent / diisobutylaluminum hydride / tetrahydrofuran; hexane / 0.5 h / Ambient temperature 8: 62 percent / trifluoroacetic acid, dimethyl sulfoxide / CH2Cl2 / 1 h / -78 °C View Scheme